code: def __init__(self, backbone):
      super().__init__()
      self.backbone = backbone
      self.projection_head = SimSiamProjectionHead(512, 512, 128)
      self.prediction_head = SimSiamPredictionHead(128, 64, 128)
  
file_path: lightly/examples/pytorch/simsiam.py
imports: import torch
  import torchvision
  from torch import nn
  from lightly.loss import NegativeCosineSimilarity
  from lightly.models.modules import SimSiamPredictionHead, SimSiamProjectionHead
  from lightly.transforms import SimSiamTransform
label_desc: Use image node_id 1 to create a new SimSiam object from inherited base classes: nn with example: obj = SimSiam(backbone)